Method of making pipe fittings



IIETHOD OF MAKING PIPE FITTINGS 3 Filed 001;. 13, 1947 IIIIIIIII Patented May 16, 1950 OFFICE METHOD OF MAKING PIPE FITTINGS William F. Keller, Milwaukee, Wis., assignor to Ladish Drop Forge Co., Cudahy, Wis., a corporation of Wisconsin Application October 13, 1947, Serial No. 779,551

2 Claims. 1

This invention relates to the manufacture of pipe fittings and refers particularly to the formation of seamless T fittings.

Seamless pipe fittings, including T's, have been made in many ways other than by casting. Solid iorgings have been drilled out, cup-shaped blanks have been worked and formed, and plain cylindrical blanks have been formed and shaped into the desired configuration. This invention deals with the formation of T's from appropriate lengths of pipe and has as its object to simplify the production of such fittings and thus lower the cost thereof without sacrificing strength or quality.

Another object of this invention is to provide a method making T fittings which results in substantially uniform wall thickness for the entire fitting, and which provides metal for the stem of the fitting by constricting the diameter of the blank during the formation of the fitting.

Another object of this invention resides in the provision of a method of making T fittings wherein the constriction of the diameter of the blank to the prescribed diameter of the head of the T occurs simultaneously with the production of a protuberance in the side of the pipe blank to be followed by the shaping and forming of the protuberance into the branch or stem of the fitting.

Still another object of this invention is to provide a method of making T fittings, the practice of which is extremely simple, thus enabling the employment of relatively unskilled labor in the production of the fittings.

with the above and other objects in view, which will appear as the description proceeds, this invention resides in the novel method and procedure substantially as hereinafter described, and

Figure 2 is a perspective view of the blank but showing the manner in which a pull-out plug is placed in position in the blank to provide a man drel for shaping the inside of the stem of the T;

Figure 3 is a perspective view of the partially iormed fitting 7 illustrating the protuberance which is formed as a. preliminary step in the formation of the stem of the T:

Figure 4 is a perspective view of the finished fitting;

Figures 5 and 6 are end views of the dies used to shape and form the blank into the head of the finished fitting and simultaneously produce the protuberance shown in Figure 3, said views respectively showing the dies open and closed;

Figure 7 is a sectional view through Figure 6 on the plane of the line 1-1; and

Figure 8 is a view similar to Figure 7, but showing the parts and the conditions after the pullout plug has been drawn through the protuberance.

Referring now particularly to the accompanying drawing in which like numerals designate like parts, the numeral Ill designates the tubular blank from which the fitting is made. This blank is merely an appropriate length of suitable seamless pipe. A hole II is cut into the pipe in preparation for the forming operation. This hole is considerably smaller than the diameter of the pipe H], which, it is important to note, is larger in diameter than the prescribed diameter of the head or main run of the finished T fitting.

In preparation for the forming operation the blank ID, with the hole ll cut therein, is heated to substantially a cherry red heat so as to give the blank suillcient ductility. The heated blanks are suitably carried or conveyed to a press, not shown except for its table l2, and in which complementary upper and lower dies I3 and it are mounted. By means of a pullout plug removably supported on the end of a handle I6 a heated blank is positioned between the dies.

The pullout plug I5 is substantially in the shape of a collar button having a round body I! of a diameter largerthan that of the hole H, a neck l8 and a head 19. The head I9 is small enough to pass through the hole ll so that the pullout plug can be hooked into the blank by means of the handle l6, as shown in Figure 2. When so inserted the head IQ of the plug protrudes through the hole II and the heated blank is suspended on the body of the plug. The head IQ of the plug is now inserted into a socket 20 slidably disposed within the upper die I3, which properly positions the blank between the dies.

The dies have round bottomed cavities which complement each other to shape and form the blank into the head or main run of the fitting. It is to be noted that the diameter of the circle defined by the round bottomed cavities of the dies when they are closed is less than the outside diameter of the blank. Consequently when the dies are brought together and onto a blank suspended in position between them by means of the collar button-like pullout plug hung from the socket 20, a constriction in the diameter of the blank takes place, thus providing metal for the simultaneous formation of a protuberance 2| shown in Figure 3.

As will appear from a. comparison of Figures 5 and 6. the protuberance is formed by drawing the metal of the blank over the body I! of the pullout plug as the upper die It descends while the socket 20 is supported against descent by means (not shown) to which its supporting rod 22 is attached. With the closure of the dies the head or main run 24 of the fitting is formed.

Also as will be seen from a comparison of Figures 5 and 6 directly after the upper die in its descent contacts the blank, the blank is brought down onto the lower die to be supported thereby.

It is to be noted that the upper die I 3 has a cylindrical recess 25 opening to its round bottomed cavity and a guideway 26 extending through the top thereof. The socket 20 slidably moves through the guideway 26 into and out of the recess 25. The diameter of the recess 25 determines the outside diameter of the stem or branch of the finished fitting. Thus after the protuberance is formed in the manner described and while the dies are held closed, the pullout plug is drawn upwardly through the protuberance by means of an upward force applied on the rod 23. During this operation the body I! of the pullout plug coacts with the cylindrical wall of the recess 25 to form and shape the protuberance 2| into the stem or branch 21 of the finished fitting.

Inasmuch as the blank is constricted during the formation of the head or main run 24 of the fitting sufiicient metal is provided for the formation of the stem or branch 21, and in addition the wall of the head or main run of the fitting may be given any desirable cross sectional shape as for instance a slight thickening of the wall at its medial portion 28 opposite its stem or branch 21. I

After the pullout plug has been drawn up into the recess 25 the upper die is raised, leaving the finished fitting resting in the lower die ll from which it may be removed in any desired manner.

From the foregoing description taken in connection with the accompanying drawing it will be readily apparent that this invention provides a method of making seamless Ts or branched fittings which, by virtue of its simplicity assures good results even though relatively unskilled labor is employed, and that the method is not limited to the strict formation of T fittings but lends itself to the production of branched fittings in which the branch is disposed" at an angle other than 90 to the main run of the fitting.

What I claim as my invention is:

1. The method of making a pipe fitting having a main run and a branch extending at an angle therefrom which comprises: cutting a hole in the side of a piece of pipe larger in outside diameter than the prescribed outside diameter of the main run of the finished fitting; placing a pullout plug having a body portion with a circular cross-section larger in diameter than the hole and a neck smaller than the hole, inside the piece of pipe with the neck protruding through the hole; suspending the piece of pipe by means of the neck on the pullout plug between open complementary upper and lower dies of the size and shape to form the main run of the fitting; closing the dies while holding the pullout plug against descent so as to simultaneously shape and form the main run of the fitting and draw the metal of the pipe over the body of the pullout plug to produce a protuberance on the side of the main run of the fitting; and drawing the pullout plug through the top of the protuberance to form and shape the protuberance into the branch of the fitting.

2. The method of making T fittings which comprises: cutting a hole in the side of a piece of pipe having an outside diameter larger than the prescribed diameter of the head of the T fitting; placing the piece of pipe between complementary forming dies shaped to define the exterior of the finished T fitting; inserting a forming plug having a body portion round in cross section and larger in diameter than the hole in the pipe, inside the piece of pipe in line with the hole therein; supporting the forming plug with the piece of pipe hanging therefrom; moving one of the formin dies relative to the forming plug in a direction to close the forming dies to contract the piece of pipe to the outside diameter of the head of the finished T fitting and at the same time draw the metal of the piece of pipe surrounding the hole therein over the body of the forming plug to form a protuberance; and effecting further relative movement between the closed forming dies and the forming plug to force the plug through the top of the protuberance to thereby enlarge the hole and shape the protuberance into the stem of the T fitting.

WILLIAM F. KELLER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 197,667 Roberts Nov. 27, 1877 1,455,440 Hofinger .Q May 15, 1923 1,850,803 Lutz Mar. 22, 1932 1,892,712 Taylor Jan. 3, 1933 2,065,915 Weston Dec. 29, 1938 2,290,965 Hodapp July 28, 1942 2,292,799 Romann Aug. 11, 1942 

